Management of excretions from incontinent patients is an ongoing and largely unsolved problem, not only in hospital and nursing home environments, but also for patients that are not hospitalized or in a care facility. Lack of control over the urinary function by incontinent patients who are not bedridden has for the most part has required the patients to wear large adult diaper pads which soon become fully sorbed and present an odor problem.
In the case of a incontinent patient lying in bed, it has largely been the practice to place an leakproof backed absorbent pad under the patient. The pad soon becomes soaked and timely changing of the soiled pad is often delayed, especially in those instances where the patient is confined to a nursing home where personnel are required to care for a large patient population that is usually the case in a hospital setting. The patient is unable to avoid contact with the wet pad, which is not only uncomfortable, but also is odorous and unsanitary and can cause undesirable skin conditions to occur such as rashes and sores.
Similarly, patients whose condition permits them to sit up in a chair or wheelchair for extended periods of time likewise must be provided with a pad to sit on to collect accidental urine excretions. Here again, changing of a pad as soon as it becomes soaked often cannot be accomplished by the patient and often results in the patient sitting on the wet pad for an extended period until a change out of the pad is ultimately accomplished after an undesirable time interval.
One asserted solution to the incontinent patient problem is shown and described in U.S. Pat. No. 4,747,166. In this patent, a pad is provided having an absorptive core encased within a polyethylene cover in which the normally uppermost layer of the cover is liquid permeable. A perforated tube centrally embedded in the absorptive core is connected via a tube to a urine collection vessel that is in turn coupled to a vacuum pump for withdrawing liquid from the pad absorbed into the central core. The core of the pad is described as having a number of perforated layers of absorbent cellulose tissue in the upper portion of the pad adjacent the upper, permeable layer of the cover, and a plurality of layers of defiberized wood pulp fluff below the cellulose layers. Another cellulose layer is provided below the layers of wood fiber fluff. Alternatively, the core of the pad may be expanded cellulose microcellular material.
Disadvantages of the system of the '166 patent include the cost of the pad, the need to periodically replace the pad, inability to effectively remove all of the liquid absorbed by the core of the pad because a certain proportion of the urine will be retained on the absorbent cellular material, the need for the perforated tube embedded in the core to be relatively rigid in order to preclude collapse of the perforations in the tube thereby imparting a degree of rigidity to the pad, and the impracticality of periodically cleaning the absorbent core of the pad with a cleaning and sterilizing agent.
In addition to the problem of accumulating and disposing of fluid wastes from a bedridden or disabled person, there is a long standing need for inexpensive and efficient apparatus for collecting a variety of fluids, or to deliver fluid from a source to a relatively large surface area in a controlled low volume perfusion transfer manner. Such areas of need include, as an example, dispersion of Treated Sewage Effluent (TSE) in a shallow subsurface underground installation serving as an alternative to a conventional leachfield, to effect evaporation or vertical dispersion of the water in a waste effluent solution, as well as to provide underground irrigation water to the root systems of plants. Another embodiment may be used to control oil slicks on ocean water or the like, as well as aspirating oil out of sand. A further use is to introduce cooled or heated air or water between the layers of structural components such as multilayered roofs, walls or floors to effect heating or cooling, or to provide positive or negative buoyancy of floating structures.